Officials in Miami say several people have been killed and cars crushed when a newly installed pedestrian bridge collapsed onto a highway on Thursday.
Florida Highway Patrol says at least five vehicles are trapped under massive slabs, with search and rescue operations underway.
It added that it does not have an exact death toll.
Construction of the 950-ton bridge was finished last Saturday, connecting Florida International University and the city of Sweetwater.
It hadn't yet opened to foot traffic.